Electrical resistance welding machine



March 24, 1931. Q L. SJLANDER 1,797,624

ELECTRlCAlJ RESTSAbCEv WELDING MACHINE Filed Aug. l2, 1929 Patented Mar.24, 1931 i 1,797,624

y UNITED STATES PATENT OFFICE CARL GUSTAF LEONARD SJ'LANDER, 0FDALSBORG, GOTTENBORG, SWEDEN ELECTRICAL RESISTANCE WELDING MACHINEApplication led Augustin, 1929, Serial No. 385,301, and in Sweden March12, 1929.

The subject of the present invention is a a long life to the electrodebearings, it Iis prefdevice for facilitating and reducing the costerable to use a pair of such rollers pressing of the drift in electricalresistance Welding against substantially diametrically opposed machines,point and seam weldingy machines points of the electrode as shown in thedrawin which rolling electrodes are used. I ing. Thus, radial pressuresof the rollers on 55 It is a known fact that the rolling electheelectrode, balance each other and furthr-- trodes are subjected to arelatively large wear more the pressure of each individual roller andupsetting of the parts coming into conmay be reduced when two areemployed. If, tact with the piece to be welded, the contact on accountof the form of the work to be surface between the electrode and thepiece welded, both electrodes cannot be provided 60 to be welded thuschanging dimensions with with rollers, a great advantage is neverthelessaccompanying change of the temperature of obtained by providing one ofsaid electrodes the piece to .be welded and the character of with suchrollers. the weld. -The vcontact surface thus has a Iclaimzl5 tendencyto become larger, at which the tem- 1. In an electrical resistancewelding ma- 65 perature falls, and the voltage of the electrichinehaving a rolling electrode; two periphcal current once properly set hasto be suc erally grooved rollers whose grooves receive cessivelyincreased causing waste of time and substantially diametrically oppositeportions loss of material. After a relatively short ofthe periphery ofsaid electrode, and spring time the electrodes have to be returned tomeans holding said rollers in engagement 70 their original form whichbrings with it loss with s aid electrode. of time and material. If theelectrodes kept t 2. In an electrical resistance welding matheir formfixed for a certain work these dischine having a rolling electrode; twoperiph' advantages would be obviated. erally grooved rollers whosegrooves receive- Atthe present invention one or more cirsubstantiallydiametrically opposite portions 76 cular rollers provided with groovesare emof the periphery of said electrode, swingable ployed, whichrollers are pressed against the arms carrying said rollers respectively,and electrodes, and which .during the rotation of spring means acting onsaid arms to hold said the latter,roll against the same and in thisrollers engaged with the electrode.

way hold them in fixed form and thus main- 3. In an electricalresistance ywelding ma- 80 tain the contact surfaces at thepredetermined chine having a rolling electrode; two periphdimensions.erally grooved rollers whose grooves receive Fig. 1 of the accompanyingdrawing is a substantially diametricall7 opposite portions 4View ofelectrodes, circular rollers vand piece of the peri hery of said eectrode', two levers` to be welded. fulcrumed Vbetween their ends, saidrollers be- -8 Fig. 2 is a section on the line A-A f ing carried bygoneend of said levers, and a Fig. 1. y I compressionV spring between theother ends l and 2 indicate the electrodes and 3, 4, 5 of said leversforjspreading said other ends,\

and 6 I above mentioned ycircular rollers. thereby holding therollers'engaged with the 40 These circular rollers are mounted each inelectrode.. s

one end of a lever or arm 13 turnable about af In witness whereof I havehereunto signed shaft-journal 14,' and between the other ends my name.-i of the arms 13 are mounted springs 7, 8 CARL GUSTA; LEONARD SJLANDEKwhich press said rollers against the elecy trodes. 9 and 10 indicatescrews for straining the springs. i l

For the purpose of the invention, it is theoretically sufficient to useone roller only to press against the rolling electrode or electrodes,but for practical reasons and to insure

